The prior art knows several different nozzles for manufacturing granulated sodium percarbonate. For example, document EP 716 640 presents a process for the production of granulated sodium percarbonate. The process uses a three-way atomiser nozzle having a central tube and two jacket tubes arranged coaxially around the central tube, the central tube extending beyond the jacket tubes by at least one radius of the central tube at the nozzle tip. One of the solutions is introduced into the central tube, second of the solutions is introduced into the annular gap formed between the central tube and the inner jacket tube, and propellant gas is introduced into the outer annular gap formed between the jacket tubes.
Publication EP 787 682 describes also a process for the production of granulated sodium percarbonate. This process uses a four-way atomiser nozzle having a central tube and three jacket tubes arranged coaxially around the central tube. In the process, one of the solutions is introduced into the central tube, the propellant gas is introduced into the annular gap formed between the central tube and the inner (=first) jacket tube, the suspension is introduced between the annular gap formed between the first and second jacket tubes and the propellant gas is introduced into the outer annular gap formed between the jacket tubes.
Document US 2006/0049281 presents a nozzle for spraying liquid substances. The nozzle includes a cylindrical nozzle body and a nozzle mouth piece. Said nozzle body includes an inner tube and an outer tube, the inner tube being connected to a supply for a substance to be sprayed, and the outer tube being connected to a supply for an atomising gas or carrier gas.
All these prior art nozzles, however, use pressurised air as atomising gas and carrier gas, as its function is to both atomise the liquids and to form the droplets. The problems associated with this are, i.e., important need for pressurised air, which is rather costly in the point of view of operation, maintenance and investment.